COL4A3 and focal segmental glomerulosclerosis: Hence, our study not only expanded the variants spectrum of COL4A4 gene and contributed to the genetic counseling and prenatal genetic diagnosis of the family, but also recommended the new classification of collagen IV nephropathies, which may be a benefit to the diagnosis, target drug treatment, and management of COL4A3/COL4A4 related FSGS, AS and GBM related diseases.